The background of the invention will be discussed in two parts.
1. Field of the Invention
The present invention relates to a pager system for use on the premises of a telephone subscriber utilizing the existing telephone wiring and telephone sets with DTMF (tone) dialing capability, with provision for an intercom function.
2. Description of the Prior Art
Home telephones have become indispensable in normal daily living for providing connections to the outside world. In the United States, within the past twenty-five years telephone wires have been pre-wired into virtually every room of every newly built residence, be it a home or apartment. Such wiring for households has normally provided capability for multiple telephone instruments with telephone connections provided in different rooms and areas for access and convenience. Yet, when it comes to providing communication between people in the same household with multiple telephone instruments, those telephones, though conveniently located and accessible, are not very useful for that purpose.
With respect to the telephone system in the residence, multiple telephone instruments on the same phone loop line can not be rung individually, that is, an incoming call rings at all instruments on the same local loop line. As a consequence, when one occupant answers the phone, only to discover that the call is for another occupant in another part of the residence, in the absence of an intercom system, there is no convenient way to notify the other party to pick up the phone. Furthermore, since telephones on the same phone loop line can not be rung individually, it has become a fundamental inconvenience in the case of multiple persons sharing one phone line with two or more telephones at different locations. A person answering a phone call bears the burden of locating the person for whom the phone call is intended. The available methods for that could be anything such as yelling or walking around. The conventional residential telephone instrument itself provides no assistance in this task.
U.S. Pat. No 4,899,378 to Hamer discloses an in-home voice announcement device that can be activated by a single tone pair of the residential telephone instruments. However, since it is effectively a voice broadcast system, it does not allow any selection of the audience. In other words, even if the whereabouts of the target person is known, the paging will be delivered to all available points, and thus disturb everybody on the premises, without discrimination. While general voice paging allows meaningful message dissemination, it has to work with an amplifier/speaker system of reasonable quality to make the voice message legible. Yet, it may still be difficult to hear in a noisy environment.
Separate intercom systems have been utilized for communication between different persons in different rooms in the same household. However, such intercom systems are totally separate and require separate wiring, that is, separate from the telephone wiring. Most dedicated intercom systems provide basically the same general paging function but still lack addressability, that is, most residential voice paging systems, such as intercom systems, are likewise announced to all intercom stations. Additionally, such systems tend to be very expensive, particularly if they are installed after the residence has been constructed. Furthermore, such intercom units are wall mounted and are less convenient for access compared to telephone instruments.
At one time, local telephone companies offered a service called Intercom, which allowed a subscriber to use the phones as an intercom. To use it, the subscriber picked up the phone and dialed one of three ring pattern choices: #51, #52 or #53. These ring patterns will connect to the central office (CO), Then the central office would ring all of the on-hook phones on the same phone line with the chosen one of the three different patterns. When the paged party picked up the phone, the intercom function could then be carried out over the telephone instruments. While this allowed a little flexibility, its coverage still included the entire premises, i.e., all phones would ring. In addition, the intercom function would not work if a connection had already been made through the CO (central office with another subscriber's phone). In other words, if a call came in to a residence, and the phone was answered, the intercom function for the phone could not then be used. Of course, for such local telephone company service, there was an installation charge and a monthly charge for the service per phone line.
A shared line telephone answering system is shown and described in U.S. Pat. No. 5,432,844, in which system there is used a master telephone answering device and extension telephone answering devices, one for each other phone in the residence. If a telephone call is answered by someone, others nearby may be paged through the extension telephone answering device from any telephone. Such a system requires a telephone answering device at each phone, thereby necessitating a large expenditure.
Other intercom systems which are usable in residential environments and do make use of at least some of the existing telephone networks are known in the prior art such as U.S. Pat. No. 4,588,861 to Teich, and U.S. Pat. No. 4,196,317 to Bartelink. However, in addition to other deficiencies, both of these systems require the use of the other two wires on the same RJ11telephone socket.
It is a feature of the present invention to provide a new and improved residential pager system utilizing the existing ring and tip telephone wiring in a home with conventional DTMF telephone instruments.
Another feature of the present invention is to provide a pager system which is selectively addressable to a given area or to a single selected room, out of two or more areas or rooms.
Another aspect of the invention is to provide a unique addressing system for the pager which address has provision for selection of distinctive signals, unique to each occupant, as well as unique to a specific room or area location.
Still another feature of the present invention is to provide a pager system which, when used in conjunction with telephone instruments, becomes an intercom system utilizing the two telephone subscriber wires.
Yet another feature of the present invention is the incorporation of the pager function into the telephone instrument itself.